The global signature system, symbolized by the GPS symbol, is a navigation system through satellites, and its primary function is to provide accurate information about the geographical location of a specific person.
There is no doubt that the system has contributed to the development of many areas such as land trips, maritime navigation, and various military tasks, as the system plays A distinctive role in the fields of surveying, that is why the system is considered one of the most used measurement tools by geodetic survey engineers due to the accuracy and validity of its data.
1. The Idea of Global Signature System
The idea of launching satellites associated with the global signature system goes back to the year 1960 by the United States of America, as the program was initially related to the US Army only, and with the increase in the percentage of aircraft accidents in the world, and the problems and difficulties related to determining the sites of aircraft crashes, an American body considered an advanced system It determines the locations of the aircraft, provided that the system is circulated to all people. By 1995 the US administration was able to equip the number of satellites needed to cover the entire surface of the Earth.
2. How the Global Signature System Works?
The global signature system has allocated 24 satellites that work continuously to cover all areas of the planet, and 4 satellites at an altitude of 20200 km from the surface of the Earth have been attached as a precaution in the event of failure of any of the main satellites, and at the present time, the United States of America is responsible for the issue of maintenance and replacement of satellites in A case of ruin or damage, or otherwise.
The mechanism of the system’s work is through the operation of a GPS receiver, where the device polarizes the signals of four satellites as a minimum so that it can calculate the distance separating the device from the satellites, which leads to determining the geographical location of the satellites, and in general, the normal global signature system determines these The process has an accuracy of 3 to 50 meters, and some practical systems can specify a millimeter accuracy, but it is not available for normal public use.